Many electronic devices today are portable. Notebook computers, ultra-portable computers, mobile phones, entertainment appliances, and navigational tools are just a few examples of portable devices. Portable devices, especially as they become smaller, are less likely to include a full-size keyboard, a tethered remote, an attached mouse, and so forth. Nevertheless, some input interface is typically needed to enable a user to control the device.
Thus, most portable devices include some kind of integrated input interface. Example integrated input interfaces include miniaturized keyboards, single buttons, touch screens, track pads, dials, directional buttons, and so forth. Each of these existing integrated input interfaces has drawbacks. For example, miniaturized keyboards, single buttons, and dials are not adept at enabling a user to control a pointer indicator of a graphical user interface (GUI). Track pads and directional buttons do enable interaction with a GUI pointer indicator, but the former can be imprecise and the latter is usually slow and inconvenient to use.
Moreover, each of these integrated input interfaces typically demands additional surface area on and/or significant volume of the device, both of which result in a larger portable device. With a touch screen, on the other hand, the face of the device does not need to be increased to accommodate an integrated input interface. Unfortunately, when an individual is attempting to interact with a touch screen, the user's finger or fingers block the details of the desired screen target. The remaining portion of the user's hand can also obscure other display portions of the touch screen. It is therefore apparent that many deficiencies still exist for conventional integrated input interfaces for portable devices.